Eli Lilly and Co. has sued Roche Holding AG’s Genentech unit, asking a court to invalidate patents used to make treatments for cancer and autoimmune diseases, and also order that Lilly's Erbitux drug doesn’t infringe the patent.

Genentech deceived the U.S. Patent Office into issuing patents known as “Cabilly” after one of the inventors, Lilly said in a complaint filed Thursday in federal court in San Francisco. Genentech claims that the process and certain starting materials used to produce Erbitux infringe parts of the patents, and is pursuing an “aggressive litigation policy to protect its products against competition,” according to the complaint.

Erbitux, made by Indianapolis-based Lilly’s ImClone unit, is approved in the United States to treat colon cancer and head and neck tumors. Lilly realized about $400 million in revenue from the drug in 2012.

“Lilly contends that it has no obligation to pay royalties on the sale of Erbitux” due to the “Cabilly patents being invalid and unenforceable, and, in any event, not infringed by Lilly,” Lilly said in the complaint.

A phone call to Genentech’s media office seeking comment about the lawsuit wasn’t immediately returned.